Anabasis is the most famous work, in seven books, of the Greek professional soldier and writer Xenophon. The journey it narrates is his best known accomplishment and "one of the great adventures in human history," as Will Durant expressed the common assessment.

Xenophon son of Gryllus, of the deme Erchia of Athens, also known as Xenophon of Athens, was a Greek historian, soldier, mercenary,and student of Socrates. While not referred to as a philosopher by his contemporaries, his status as such is now a topic of debate. He is known for writing about the history of his own times, the late 5th and early 4th centuries BC, especially for his account of the final years of the Peloponnesian War. His Hellenica, which recounts these times, is considered to be the continuation of Thucydides’ History of the Peloponnesian War. His youthful participation in the failed campaign of Cyrus the Younger to claim the Persian throne inspired him to write his most famous work, Anabasis.